Dr. Hornberger began her talk by showing a pie chart explaining what
the breakdown of the stuff that goes into a landfill is. Fully twenty percent
of a typical landfill is plastics by volume. This is a huge quantity of material,
much of which is used drink containers. Finding ways to recycle this material
is a golden opportunity for a plastics engineer.

Dr. Hornberger explained that on the East coast a lot of the soda bottles
end up being made into carpets, a good use for the plastic. Since transportation
is a major percentage of the price of recycling plastic, it is not cost effective
for West Coast plastics to be used in this way. Instead that material is
shipped off to China, and try as she might, she has not been able to find
out what happens to it when it gets there.

Looking around for a local use for recycled plastic, Dr. Hornberger
came across the idea of using it to make the plastic components used by the
building industry. She had students make experimental pieces that could be
used in place of the rebar shelves and the cones used in making poured concrete
walls and floors. They did all the steps, from collecting bottles, grinding
them up, washing the plastic, making the molds and using them in the lab
to manufacture useful parts.

Since making prototypes Dr. Hornberger has shopped them around to many
plastic companies to see if they want to commercialize the process, now that
she has proved that it is very feasible. It turns out that all of the plastic
companies are owned by the oil companies, and this has had a significant
impact on their attitude towards other sources of material to run their
production lines. She often gets a response that she characterized as
"stonewalling" when she asks them to try recycled source material.